the president promising fast action to stop an epidemic of gun violence. >> i will use all the powers of this office to help advance efforts aimed at preventing more tragedies like this. >> and tonight, we hear from people on the other side, who believe the way to defend children is to arm their teachers. >>> holiday headache. as millions of americans begin their holiday travel, a blizzard is on a collision course. creating 50-mile-per-hour winds and delays. >>> prison break.